Pitch Modulation for Altered Guitar Tunings变吉他调音音高调制.docVIP

Pitch Modulation for Altered Guitar Tunings Paul Ternes Andy Eden ECE 445 Spring 2006 I. Introduction For those interested in performing music through the use of stringed instruments such as a guitar it has always been important to be able to modify the tuning in order to create a wide array of chords. Normal tuning of a guitar sets the five strings to the notes of EADGBE, yet in order to more easily play certain chord arrangements tuning all of the strings, or even a single string, down or up sometimes becomes necessary. While both of us are not only avid music listeners, but also music performers we are very excited to be able to put our electrical engineering knowledge to work to make this task of alternate tunings simpler and more efficient. In our project we intend to create a digital system combined with an optical sensor that will take the notes of a guitar and electronically tune one or all of them down or up dependant on user input, and will output this change on the amplifier. The tuning will occur in intervals of half steps in an amount set by the user. This process will not only reduce user error in tuning but will also save time and open opportunities for faster chord transitions even during the middle of songs. Benefits: Automatic digital up or down tuning at half step intervals. Ability to tune not only all of the strings but one string for optional “drop D” tuning. Fast transition from original tuning to the next desired tuning. Simple interface to select desired mode and tuning. Application expandable to other instruments such as bass guitar. Features: Optical sensor attached to base of strings to sense when specific strings are being played. Tuning box easily connected through guitar chord then to amplifier. Conversion of tuning done in digital frequency domain to simplify process. II. Design Block Description: Optical Sensor: It will be necessary, for the circuit to determine if the heaviest gauge string is being played. This will b